Github user cestella commented on a diff in the pull request:

    https://github.com/apache/incubator-metron/pull/352#discussion_r87657821
  
    --- Diff: 
metron-analytics/metron-profiler/src/main/java/org/apache/metron/profiler/bolt/ProfileBuilderBolt.java
 ---
    @@ -246,6 +247,8 @@ private void flush(Tuple tickTuple) {
         // clear the execution state to prepare for the next window
         executor.clearState();
     
    +    profileConfig.getTickUpdate().forEach((var, expr) -> 
executor.assign(var, expr, new HashMap<>()));
    --- End diff --
    
    I do not need to access the message, but rather just the internal state.  I 
have made a modification which does what I think it should do with some 
comments.  If you see issues, I'd love it if you could let me have it. :)
    
    Taking a step back, the purpose of this is in situations where we need to 
do things like capture a trailing window of state.  In the instance of Median 
Absolute Deviation it is required because we need not just the distribution of 
the values, but also the distribution of the DEVIATION of the value from the 
median (which is the median of the values of the trailing window).  That window 
can be updated upon tick.  So, for instance, if we want 3 hours lookback, at 
hour 4, we'd have hours 1, 2 and 3.  At hour 5, we'd want hours 2, 3, and 4 and 
so on.  Constructing this trailing window lead me to this.  I could have 
captured this state internally in memory, but that had the issue that internal 
state for the window would be removed for the entire trailing window upon 
worker crash/restart.



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